Power delivery circuitry

ABSTRACT

A memory device may include a memory system and an energy storage device. Additionally, the energy storage device may supply a first power to the memory system when a second power from a power supply is eliminated or insufficient.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a Continuation of U.S. patent application Ser. No.15/900,553 filed on Feb. 20, 2018, which is a Continuation of U.S.patent application Ser. No. 15/665,062 filed on Jul. 31, 2017, now U.S.Pat. No. 9,922,683 issued on Mar. 20, 2018, which is a continuation ofand claims priority to U.S. patent application Ser. No. 15/169,075 filedon May 31, 2016, now U.S. Pat. No. 9,747,957 issued on Aug. 29, 2017,all of which are herein incorporated by reference.

BACKGROUND 1. Field of the Invention

Embodiments of the present invention relate generally to the field ofmemory devices and other systems and more particularly, to systems andmethods of providing power for memory devices and other systems.

2. Description of the Related Art

Computer systems and other electrical systems generally include one ormore memory devices. Memory devices generally include circuits (e.g.,integrated circuits, semiconductor circuits, etc.) configured to storedata. For example, the memory devices may include volatile and/ornon-volatile memory. Examples of types of volatile memory, which requirepower to retain stored information, include random-access memory (RAM),dynamic random access memory (DRAM), synchronous dynamic random accessmemory (SDRAM), among others. Non-volatile memory does not require powerto retain stored information and can include read only memory (ROM),flash memory (e.g., NAND flash memory and NOR flash memory), phasechange random access memory (PCRAM), resistive random access memory(RRAM), magnetic random access memory (MRAM), and so forth.

Solid state drives (SSDs) may be formed with various types of memorydevices (e.g., solid state memory devices). Unlike hard disk drives(HDDs), solid state drives do not include moving parts, and thereforemay not be susceptible to vibration, shock, magnetic fields, etc., andmay have reduced access times and latency. A solid state drive may beformed from volatile memory devices and/or non-volatile memory devices.For example, a solid state drive may be a NAND flash memory device thatdoes not include an internal battery. In certain configurations, thesolid state drive may be connected to an external power supply.Unfortunately, power requirements (e.g., temporary power requirements)of the solid state drive may exceed the power supplying capacity of theexternal power supply. As a result, solid state drives may experience anincrease in latency (i.e., response time) during periods when powerdemand of the solid state drive exceeds the power supplying capacity ofthe external power supply. Further, temporary power outages of theexternal power supply may result in a loss of data waiting to be storedin the memory, or an interruption in reading data from the memory.

Moreover, when a solid state drive includes an internal power storagedevice, such as a high voltage backup capacitor, the design may be costprohibitive for many applications of the solid state drive. For example,the high voltage backup capacitor may include a dedicated chargingcircuit and a dedicated discharging circuit. The additional circuitrymay increase costs associated with providing backup or supplementalpower to the solid state drive, and the additional circuitry may alsopopulate valuable space on a printed circuit board of the solid statedrive.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of a system having an external power supplyand memory device with power delivery circuitry, in accordance with anembodiment;

FIG. 2 is a block diagram of a system having an external power supplyand memory device with power delivery circuitry, illustrating anembodiment of the power delivery circuitry;

FIG. 3 is a block diagram of a system having an external power supplyand memory device with power delivery circuitry, illustrating anotherembodiment of the power delivery circuitry;

FIG. 4 is a block diagram of a system having an external power supplyand memory device with power delivery circuitry, illustrating anotherembodiment of the power delivery circuitry;

FIG. 5 is a graph illustrating voltage inputs and outputs of the systemof FIGS. 2 and 3, in accordance with an embodiment;

FIG. 6 is a graph illustrating voltage inputs and outputs of the systemof FIG. 4, in accordance with an embodiment; and

FIG. 7 is a flow diagram illustrating operation of the power deliverycircuitry of the memory device of FIG. 4, in accordance with anembodiment.

DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS

Embodiments of the present disclosure are directed to a system includinga memory device having power delivery circuitry that delivers power tothe system when a power source (e.g., an external power source) becomesunavailable. For example, the memory device may include an onboardenergy storage component that stores available input power (i.e.,energy) of the external power source in the energy storage componentwhen the external power source provides power to the memory device. Inother words, when the external power supply operates under normalconditions, the onboard energy storage component of the memory devicemay draw and store power from the external power supply.

Thereafter, when the external power supply is removed from the system,energy stored in the onboard energy storage component may be releasedand used by the memory device. In this manner, the memory device maycontinue operating for a period of time after removal of the externalpower supply. Further, when the memory device demands an amount of powerin excess of the power limit of the external power supply, additionalenergy stored in the onboard energy storage component may be releasedand used by the memory device. In this manner, the memory device mayutilize more power than the external power supply is capable ofproviding without overloading the external power supply. As discussed indetail below, then energy storage component and the power deliverycircuitry may enable improved performance of the memory device. Forexample, the energy storage component and the power delivery circuitrymay enable a reduction in latency (i.e., response time) of the memorydevice. In certain embodiments, the power delivery circuitry may also beutilized as a power backup system. While the present embodimentsdescribe the power delivery circuitry in the context of a memory device,it should be noted that the power delivery circuitry described below mayalso be used with other systems that draw power from a power supply. Forexample, the disclosed power delivery circuitry may be used with a videocard, a personal computer motherboard, a cellular phone, or othersystem.

Referring now to the drawings, FIG. 1 is a block diagram that depicts asystem 10 including a memory device 12 powered by an external powersupply 14. The system 10 may be any of a variety of systems, such asthose used in a personal computer, pager, cellular phone, personalorganizer, control circuit, laptop computer, digital camera, digitalmedia player, etc. The memory device 12 may be any of a variety ofmemory devices configured to store data, such as a solid state drive. Aswill be appreciated, the external power supply 14 provides power to thememory device 12 to enable operation of the memory device 12.

In the illustrated embodiment, the memory device 12 (e.g., solid statedrive) includes a memory system 16 and power delivery circuitry 18. Thepower delivery circuitry 18 will be described in further detail below.As shown, the memory system 16 includes a controller 20, an interface22, and memory arrays 24 (e.g., solid state memory arrays). Thecontroller 20 communicates with the memory arrays 24 to read, write,and/or erase data on the memory arrays 24. Additionally, the controller20 may communicate with another system or device coupled to the memorydevice 12 or the system 10. For example, the controller 20 maycommunicate with another system or device through the interface 22. Assuch, the interface 22 may be configured to transmit data, power,input/output signals, or other types of signals. In certain embodiments,the interface 22 may be an integrated drive electronics (IDE) interface,an advanced technology attachment (ADA) interface, a serial advancedtechnology attachment (SATA) interface, a parallel advanced technologyattachment (PATA) interface, or other type of interface.

As mentioned above, the memory device 12 includes power deliverycircuitry 18. The power delivery circuitry 18 is configured to deliverpower from the external power supply 14 to the memory system 16 of thememory device 12. Additionally, in certain embodiments, an energystorage device 26 may store energy supplied by the external power supply14, and the stored energy may be released and delivered to the powerdelivery circuitry 18 when the external power supply 14 is removed fromthe memory device 12 and/or a power demand of the memory system 16exceeds the power supplying limits of the external power supply 14. Forexample, the energy storage device 26 may be a battery, a capacitor, asuper-capacitor, or other type of energy storage. In the mannerdescribed below, the energy storage device 26 may draw and storeavailable input energy from the external power supply 14 when the memorydevice 12 is not using all of the available power supplied by theexternal power supply 14 or when the memory system 16 is idle.Thereafter, during events when the memory system 16 demands a level ofpower in excess of the power supply limit of the external power supply14, or when the external power supply 14 is removed from the memorydevice 12, the energy stored within the energy storage device 26 may bereleased and delivered, along with or as a backup to the power from theexternal power supply 14, to the memory system 16 by the power deliverycircuitry 18.

For example, in one embodiment, the external power supply 14 may becapable of supplying 200 mW of power to the memory device 12. However,the memory system 16 (e.g., solid state drive) of the memory device 12may have idle periods or other operational periods when the memorysystem 16 does not use 200 mW. Instead, the memory system 16 may operateusing less than 200 mW (e.g., 150 mW, 100 mW, or less power). Duringsuch idle or operational periods, the power delivery circuitry 18 maysupply the less than 200 mW of power demanded by the memory system 16,and the energy storage device 26 may use additional power from theexternal power supply 14 to store energy resulting from the additionalpower provided to the energy storage device 26. If the memory system 16later demands a power supply in excess of 200 mW (e.g., in excess of thepower supply limit of the external power supply 14), the power deliverycircuitry 18 may deliver the 200 mW supplied by the external powersupply 14 along with additional power from the energy storage device 26to meet the demand of the memory system 16. For example, if the memorysystem 16 demands 225 mW during a peak workload of the memory system 16,the power delivery circuitry 18 may simultaneously deliver 200 mWsupplied by the external power supply 14 and 25 mW supplied by theenergy storage device 26 to the memory system 16. As a result,performance of the memory system 16 may be improved. More specifically,the memory system 16 may not throttle performance back to operate withinthe power supply limit of the external power supply 14. Instead, thememory system 16 may perform a data transaction at a faster rate, andlatency of the memory system 16 may be reduced. Additionally, asdiscussed in greater detail below, the energy storage device 26 may alsoprovide backup power to the power delivery circuitry 18 when theexternal power supply 14 is removed from the memory device 12.

FIGS. 2-4 are block diagrams of the system 10 having the external powersupply 14 and the memory device 12, illustrating various embodiments ofthe power delivery circuitry 18 of the memory device 12. Morespecifically, the embodiments shown in FIGS. 2-4 illustrate variouscircuit topologies of the energy storage device 26. For example, FIG. 2illustrates an embodiment of the energy storage device 26 including afeed-forward capacitor 28. It may be appreciated that the feed-forwardcapacitor 28 may be substituted with any other two-terminal energystorage device, such as a battery. Further, the feed-forward capacitor28 may include a capacitance range between 100 uF and 2 F for a solidstate drive memory device 12.

The power delivery circuitry 18 may include a step-down type voltageregulator to convert voltage from the external power supply 14 to avoltage that meets voltage requirements of the memory system 16. It maybe appreciated that the step-down type voltage regulator of the powerdelivery circuitry 18 may include a buck mode DC-to-DC converter, a lowdropout regulator (LDO), a buck-boost DC-to-DC converter operating inbuck mode, or any other step-down type voltage regulator. By way ofexample, the external power supply 14 may provide five volts to thepower delivery circuitry 18, and the power delivery circuitry 18 maystep-down the five volt supply to a 3.3 volt operating level of thememory system 16. While the memory system 16 ultimately receives thestepped-down voltage from the power delivery circuitry 18, thefeed-forward capacitor 28 may receive the full voltage from the externalpower supply 14 to charge the feed-forward capacitor 28.

During events when the external power supply 14 is removed from thepower delivery circuitry 18 and the feed-forward capacitor 28, such asduring a power outage, the feed-forward capacitor 28 may provide backuppower to the memory system 16. By way of example, when the externalpower supply 14 is removed from the memory device 12, the feed-forwardcapacitor 28 will attempt to maintain an output of the power deliverycircuitry 18 at a constant level. Further, to enable the feed-forwardcapacitor 28 to provide the backup power, an isolation switch 29 may beprovided between the external power supply 14 and the power deliverycircuitry 18 and energy storage device 26. When the external powersupply 14 stops providing power to the memory device 12, the switch 29may be opened to avoid a short circuit to ground from the output of theexternal power supply 14.

FIG. 3 illustrates an embodiment of the energy storage device 26including the feed-forward capacitor 28, a current limiting resistor 30,and a discharge switch 32. The current limiting resistor 30 may limitin-rush current into the feed-forward capacitor 28 when the feed-forwardcapacitor 28 is charging. To transmit the current through the currentlimiting resistor 30, the discharge switch 32 may remain open duringcharging of the feed-forward capacitor 28. Additionally, to reduce anyenergy lost as heat to the current limiting resistor 30 while thefeed-forward capacitor 28 discharges, the discharge switch 32 may close.With the discharge switch 32 closed during a discharge operation, thecurrent provided from the feed-forward capacitor 28 to the powerdelivery circuitry 18 may avoid flowing through the current limitingresistor 30. It may be appreciated that the current limiting resistor 30and the discharge switch 32 may be positioned on either side of thefeed-forward capacitor 28, and the discharge switch 32 may be any typeof switching device.

During events when the external power supply 14 is removed from thepower delivery circuitry 18 and the energy storage device 26, such asduring a power outage, the discharge switch 32 may close and thefeed-forward capacitor 28 may provide backup power to the memory system16 via the power delivery circuitry 18. Further, to enable thefeed-forward capacitor 28 to provide the backup power, the isolationswitch 29 may be provided between the external power supply 14 and thepower delivery circuitry 18 and the energy storage device 26. When theexternal power supply 14 stops providing power to the memory device 12,the switch 29 may be opened to avoid a short circuit to ground from theoutput of the external power supply 14.

Additionally, in some control schemes, the discharge switch 32 and thecurrent limiting resistor 30 may operate as a pre-charge circuit. Insuch a control scheme, the discharge switch 32 may remain open during abrief period of time after the external power supply 14 is coupled tothe memory device 12. The current limiting resistor 30 may limit thein-rush current supplied to the feed-forward capacitor 28, and, once thefeed-forward capacitor 28 reaches an adequate charge state, thedischarge switch 32 may be closed to provide a more direct flow ofcurrent to the feed-forward capacitor 28. The discharge switch 32 mayremain closed until an additional pre-charge event is desirable, atwhich point the discharge switch 32 may open again.

FIG. 4 illustrates an embodiment of the energy storage device 26including the feed-forward capacitor 28, a grounding switch 34, and anoutput switch 36. During charging operations of the feed-forwardcapacitor 28, the grounding switch 34 may be closed, while the outputswitch 36 is open. This switching strategy couples one end of thefeed-forward capacitor 28 to ground and the other end of thefeed-forward capacitor 28 to the external power supply 14 during thecharging operations. Alternatively, during a discharging operation, thegrounding switch 34 may be opened, while the output switch 36 is closed.This switching strategy couples the end of the feed-forward capacitor28, which was previously coupled to ground, to an output of the powerdelivery circuitry 18. In providing such a switching strategy during thedischarging operations, an input voltage to the power delivery circuitry18 provided by the feed-forward capacitor 28 is effectively boosted fromthe voltage of the external power supply 14 to the voltage of theexternal power supply 14 in addition to the voltage at the output of thepower delivery circuitry 18. Further, to enable the feed-forwardcapacitor 28 to provide backup power, the isolation switch 29 may beprovided between the external power supply 14 and the power deliverycircuitry 18 and the energy storage device 26. When the external powersupply 14 stops providing power to the memory device 12, the switch 29may be opened to avoid a short circuit to ground from the output of theexternal power supply 14.

Because the energy storage device 26 of FIG. 4 provides an increasedvoltage level during the discharging operations of the feed-forwardcapacitor 28, the energy storage device 26 may provide an extendedamount of time during which the feed-forward capacitor 28 is able toprovide backup power for the memory device 12. This may be a result ofan extended amount of time for the voltage provided by the feed-forwardcapacitor 28 to fall below the output voltage level of the powerdelivery circuitry 18. Additionally, the voltage boost provided when thegrounding switch 34 is opened and the output switch 36 is closed mayalso provide a power boost at the input of the power delivery circuitry18 when the external power supply 14 does not provide a sufficient powerlevel to the memory system 16 for a brief period of time. For example,when power demands of the memory system 16 exceed the capabilities ofthe external power supply 14, the feed-forward capacitor 28, inconjunction with the grounding switch 34 and the output switch 36, mayprovide a temporary power boost to the memory system 16 to enable thememory system 16 to operate with greater efficiency. While FIGS. 2-4 aredepicted as separate embodiments, it may be appreciated that combiningelements of FIGS. 2-4 with each other is also conceived. For example,the current limiting resistor 30 and the discharge switch 32 of FIG. 3may be used in combination with the grounding switch 34 and the outputswitch 36 of FIG. 4.

FIG. 5 is a graph 40 illustrating voltage values 42 over time 44 for aninput voltage to the power delivery circuitry 18 and an output voltagefrom the power delivery circuitry 18 of the memory devices 12illustrated in FIGS. 2 and 3. In the graph 40, the input voltage isrepresented by line 46 and the output voltage is represented by line 48.Additionally, the line 46 represents the voltage 42 provided by theexternal power supply 14 or the feed-forward capacitor 28 over the time44. Similarly, the line 48 represents the voltage 42 provided to thememory system 16 from the power delivery circuitry 18 over the time 44.

At time 50, the external power supply 14 may be removed from the memorydevice 12. For example, the external power supply 14 may experience apower outage at the time 50 and/or the isolation switch 29 may beopened. At this time, the feed-forward capacitor 28 may discharge toprovide the voltage 42 to the power delivery circuitry 18. The voltageoutput of the feed-forward capacitor 28 may gradually diminish as thefeed-forward capacitor 28 discharges. Discharging of the feed-forwardcapacitor 28 may be represented by the line 46 between the time 50 andtime 51. At the time 51, the voltage provided by the feed-forwardcapacitor 28 may fall below the output voltage of the step-down typevoltage regulator of the power delivery circuitry 18. Once the voltage42 provided by the feed-forward capacitor 28 falls below the outputvoltage, the feed-forward capacitor 28 may rapidly discharge until thecharge stored on the feed-forward capacitor 28 is entirely depleted.

The line 48, which represents the voltage applied to the memory system16 after step-down via the power delivery circuitry 18, may maintain aconstant voltage level during the discharging period of the feed-forwardcapacitor 28 between the times 50 and 51. When the time 51 is reached,and the voltage provided by the feed-forward capacitor 28 falls belowthe voltage level of the line 48, the line 48 may track the rapiddischarge of the feed-forward capacitor 28 until the voltage level ofthe line 48 reaches zero potential. In this manner, the step-down typevoltage regulator of the power delivery circuitry 18 may cease operatingproperly at the time 51, and the feed-forward capacitor 28 may ceaseproviding sufficient voltage for the memory system 16 to operate.

FIG. 6 is a graph 52 illustrating the voltage values 42 over the time 44for an input voltage to the power delivery circuitry 18 and an outputvoltage from the power delivery circuitry 18 of the memory device 12illustrated in FIG. 4. In the graph 52, the input voltage is representedby line 54 and the output voltage is represented is represented by line56. Additionally, the line 54 represents the voltage 42 provided by theexternal power supply 14 or the feed-forward capacitor 28 over the time44. Similarly, the line 56 represents the voltage 42 provided to thememory system 16 from the power delivery circuitry 18 over the time 44.

At the time 53, the external power supply 14 may be removed from thememory device 12. For example, the external power supply 14 mayexperience a power outage at the time 53 and/or the isolation switch 29may be opened. At this time, the grounding switch 34 may open and theoutput switch 36 may close, and the removal of the external power supply14 may result in the feed-forward capacitor 28 discharging to providethe voltage 42 to the power delivery circuitry 18. Due to a leg of thefeed-forward capacitor 28 switching from ground to the output of thepower delivery circuitry 18, the voltage 42 of the line 54 may beincreased from the voltage of the external power supply 14 to thevoltage of the external power supply 14 in addition to a voltage at theoutput of the power delivery circuitry 18. The increase in the voltage42 is represented by a voltage spike at the time 53 in FIG. 6.

The voltage output of the feed-forward capacitor 28 may graduallydiminish as the feed-forward capacitor 28 discharges. Discharging of thefeed-forward capacitor 28 may be represented by the line 54 between thetime 53 and time 58. At the time 58, the voltage provided by thefeed-forward capacitor 28 may fall below the output voltage of thestep-down type voltage regulator of the power delivery circuitry 18.Once the voltage provided by the feed-forward capacitor 28 falls belowthe output voltage, the feed-forward capacitor 28 may rapidly dischargeuntil the charge stored on the feed-forward capacitor 28 is entirelydepleted. It may be appreciated that because the voltage 42 provided bythe feed-forward capacitor 28 at the time 53 is greater in FIG. 6relative to the voltage 42 provided by the feed-forward capacitor 28 atthe time 50 in FIG. 5, a time period between the times 53 and 58 may begreater than a time period between the times 50 and 51. That is, theenergy storage device 26 illustrated in FIG. 4 may take a greater amountof time to discharge than the energy storage devices 26 illustrated inFIGS. 2 and 3. Accordingly, the energy storage device 26 illustrated inFIG. 4 and represented by the graph 52 may provide sufficient voltagefor the memory system 16 to operate for a longer period of time than theenergy storage devices 26 illustrated in FIGS. 2 and 3 under similaroperating conditions.

Further, the line 56, which represents the voltage applied to the memorysystem 16 after step-down via the power delivery circuitry 18, maymaintain a constant voltage level during the discharging period of thefeed-forward capacitor 28 between the times 53 and 58. When the time 58is reached, and the voltage provided by the feed-forward capacitor 28falls below the voltage level of the line 56, the line 56 may track therapid discharge of the feed-forward capacitor 28 until the voltage levelof the line 56 reaches zero potential. In this manner, the step-downtype voltage regulator of the power delivery circuitry 18 may ceaseoperating properly, and the feed-forward capacitor 28 may ceaseproviding sufficient voltage for the memory system 16 to operate.

FIG. 7 is a flow diagram 70 illustrating operation of the energy storagedevice 26 of the memory device 12 of FIG. 4. Initially, at block 72, acharge mode signal is received by the energy storage device 26. Thecharge mode signal may indicate to the energy storage device 26 that theexternal power supply 14 is operating under a condition that enables theexternal power supply 14 to charge the energy storage device 26. Forexample, the energy storage device 26 may receive the charge mode signalwhen the external power supply 14 resumes providing power to the memorydevice 12 or the memory system 16 reduces a power demand to a level thatthe external power supply 14 is capable of meeting.

Upon receiving the charge mode signal, at block 74, the energy storagedevice 26 may be instructed to couple one end of the feed-forwardcapacitor 28 to ground by closing the grounding switch 34, while theoutput switch 36 is maintained in an open position. This position may bemaintained during a charging operation of the feed-forward capacitor 28,and the grounding switch 34 coupling the feed-forward capacitor 28 toground enables the voltage stored on the feed-forward capacitor 28 to beequal to the voltage provided by the external power supply 14 ratherthan a difference between the voltage of the external power supply 14and a voltage at an output of the power delivery circuitry 18. In thismanner, at block 76, the external power supply 14 may provide chargingpower to the feed-forward capacitor 28 until a backup or boost powersignal is received by the energy storage device 26.

For example, at block 78, the energy storage device 26 may receive abackup or boost power signal. The backup or boost power signal mayinstruct the energy storage device to transition to a discharge mode.Such a transition may be provided when the memory device 12 receives anindication that the external power supply 14 is no longer providingpower to the memory device 12, or that the external power supply 14 isnot providing sufficient power to meet the demands of the memory system16 of the memory device 12.

After receiving the backup or boost power signal, the energy storagedevice 26, at block 80, may couple the one end of the feed-forwardcapacitor 28, which was previously coupled to ground, to an output ofthe power delivery circuitry 18 by closing the output switch 36 andopening the grounding switch 34. Additionally, the isolation switch 29may also be opened to prevent a short circuit to ground at the output ofthe external power supply 14. Because the feed-forward capacitor 28 istransitioned from being coupled to ground to being coupled to the outputof the power delivery circuitry 18, the voltage provided to the input ofthe power delivery circuitry 18 may be equal to the voltage of theexternal power supply 14 in addition to the voltage of the output of thepower delivery circuitry 18.

The resulting voltage may be applied to the power delivery circuitry 18,at block 82, until the feed-forward capacitor 28 is completelydischarged, or until the energy storage device 26 receives an exitbackup or boost signal at block 84. The exit backup or boost signal maybe provided be provided to the energy storage device 26 when, forexample, the memory device 12 is turned off. Additionally, in someinstances, immediately upon receiving an exit backup or boost modesignal, at block 84, the energy storage device 26 may receive a chargemode signal at block 72 to repeat the charging and discharging processof the flow diagram 70.

As described in detail above, embodiments of the present disclosure aredirected to a system, such as the memory device 12, having powerdelivery circuitry 18 that in operation provides power from the externalpower supply 14 and/or the energy storage device 26 to the memory system16. The energy storage device 26 of the memory device 12 includes thefeed-forward capacitor 28, and the energy storage device 26 may includethe current limiting resistor 30, the discharge switch 32, the groundingswitch 34, and/or the output switch 36, which are components used toassist in charging and discharging operations of the energy storagedevice 26. The energy storage device 26 may provide backup power to thememory device 12 when the external power supply 14 is removed, and/orthe energy storage device 26 may provide boosting power when an outputof the external power supply 14 is not sufficient to operate the memorysystem 16. As a result, the energy storage device 26 may enable improvedperformance of the memory device 12.

While the subject matter described herein may be susceptible to variousmodifications and alternative forms, specific embodiments have beenshown by way of example in the drawings and have been described indetail herein. However, it should be understood that the presentlydescribed subject matter is not intended to be limited to the particularforms disclosed. Rather, the described subject matter is to cover allmodifications, equivalents, and alternatives falling within the spiritand scope of the invention as defined by the following appended claims.

What is claimed is:
 1. A method comprising: charging an energy storagedevice via a first power from a power supply, wherein the energy storagedevice is coupled between an input of power delivery circuitry of amemory device and an output of the power delivery circuitry; receiving,in the power delivery circuitry, the first power from the power supply,a second power from the energy storage device, or both; and delivering athird power, via the power delivery circuitry, to a memory system of thememory device.
 2. The method of claim 1, wherein the energy storagedevice is directly coupled to the input of the power delivery circuitry.3. The method of claim 1, wherein charging comprises charging the energystorage device through a resistor configured to regulate the charging.4. The method of claim 1, comprising directly coupling the energystorage device to the input of the power delivery circuitry via a switchconfigured to bypass a resistor.
 5. The method of claim 1, wherein thethird power comprises a combination of the first power and the secondpower.
 6. The method of claim 1, wherein the memory system comprises asolid state memory system.
 7. The method of claim 1, wherein the powerdelivery circuitry comprises a direct current (DC) to DC voltageconverter.
 8. The method of claim 7, wherein the DC to DC voltageconverter comprises a buck mode DC to DC converter.
 9. The method ofclaim 1, comprising supplementing the first power to the power deliverycircuitry with the second power.
 10. A method of manufacturing a memorydevice comprising: coupling power delivery circuitry to a memory system;and coupling an energy storage device between an input of the powerdelivery circuitry and an output of the power delivery circuitry,wherein the energy storage device is configured to supply a first powerto the input energy storage device, and wherein the output of the powerdelivery circuitry is configured to provide a second power to the memorysystem.
 11. The method of claim 10, wherein the energy storage device iscoupled in parallel with the power delivery circuitry.
 12. The method ofclaim 10, comprising coupling the input of the power delivery circuitryto a power supply of the memory device.
 13. The method of claim 12,wherein the power delivery circuitry is configured to receive a thirdpower from the power supply.
 14. The method of claim 10, whereincoupling an energy storage device between the input of the powerdelivery circuitry and the output of the power delivery circuitrycomprises coupling a resistor between input of the power deliverycircuitry and the energy storage device.
 15. The method of claim 14,comprising configuring a switch to operatively bypass the resistor. 16.The method of claim 10, wherein the energy storage device comprises afeed forward capacitor.
 17. A method of manufacturing an electronicdevice comprising: coupling power delivery circuitry to one or morememory arrays, wherein the power delivery circuitry is configured toreceive a first power from a power supply and supply a second power tothe one or more memory arrays; coupling a first electrical connection ofan energy storage device to an input of the power delivery circuitry,wherein the energy storage device is configured to supply a third powerto the power delivery circuitry; and coupling a second electricalconnection of the energy storage device to a ground reference via aswitch, wherein the switch is configured to operatively couple thesecond electrical connection of the energy storage device and the groundreference during charging of the energy storage device.
 18. The methodof claim 17, comprising coupling the second electrical connection of theenergy storage device to an output of the power delivery circuitry via asecond switch, wherein the second switch is configured to operativelycouple the second electrical connection of the energy storage device andthe output of the power delivery circuitry during discharge of theenergy storage device.
 19. The method of claim 17, wherein the secondpower comprises only the third power.
 20. The method of claim 17,wherein the power delivery circuitry comprises a step down voltageregulator.